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The Epstein-Barr virus (EBV) is best known as the cause of mononucleosis, the ubiquitous “kissing disease” that most people contract at some point in their life. But in rare instances, this virus plays a more sinister role as the impetus of lymphomas, cancers that affect the white blood cells known as lymphocytes.

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The Epstein-Barr virus (EBV) is best known as the cause of mononucleosis, the ubiquitous “kissing disease” that most people contract at some point in their life. But in rare instances, this virus plays a more sinister role as the impetus of lymphomas, cancers that affect the white blood cells known as lymphocytes. EBV-associated lymphomas account for about 40% of Hodgkin lymphomas, 20% of diffuse large B-cell lymphomas, and more than 90% of natural killer/T-cell lymphomas. This latter type of lymphoma typically has a very poor prognosis even with the “standard of care” lymphoma treatments such as chemotherapy and/or radiation.

When these interventions fail, the only curative approach is an allogeneic hematopoietic stem cell transplant from a healthy donor, a treatment that’s tough on patients’ bodies and carries significant risks, says Lauren P. McLaughlin, M.D., a pediatrician specializing in hematology and oncology at Children’s National in Washington, D.C. Patients who receive these allogenic transplants are immune-compromised until the donor cells engraft; the grafts can attack patients’ healthy cells in a phenomenon called graft versus host disease; and if patients relapse or don’t respond to this treatment, few options remain.

To help improve outcomes, Dr. McLaughlin and colleagues tested an addition to the allogeneic hematopoietic stem cell transplant procedure for patients with EBV-associated lymphomas: infusion of a type of immune cell called T cells specifically trained to fight cells infected with EBV.

Dr. McLaughlin, along with Senior Author Catherine M. Bollard, M.D., M.B.Ch.B., director of the Center for Cancer and Immunology Research and the Program for Cell Enhancement and Technologies for Immunotherapy at Children’s National, and colleagues tested this therapy in 26 patients treated at Children’s National or Baylor College of Medicine. They published these results online on Sept. 27, 2018, in the journal Blood. The study was a Phase I clinical trial, meaning that the therapy was tested primarily for safety, with efficacy as a secondary aim.

Seven patients who received the therapy had active disease that had not responded to conventional therapies. The other 19 were patients deemed to be at high risk for relapse.

Before each patient received their stem cell transplant, their donors gave an additional blood sample to generate the cancer-fighting T cells. Over the next 8 to 10 weeks, the researchers painstakingly manufactured the immune cells known as T-cells that specifically targeted EBV, growing these cells into numbers large enough for clinical use. Then, as early as 30 days after transplant, the researchers infused these T-cells into patients administering at least two doses, spaced two weeks apart.

Over the next several weeks, the researchers at CNMC and Baylor College of Medicine monitored patients with comprehensive exams to see how they fared after these transplants. The results showed that adverse effects from the treatment were exceedingly rare. There were no immediate infusion-related toxicities to the T-cell therapy and only one incident of dose-limiting toxicity.

This therapy may be efficacious, depending on the individual patients’ circumstances, Dr McLaughlin adds. For those in complete remission but at high risk of relapsing, the two-year survival rate was 78%, suggesting that the administration of this novel T-cell therapy may give the immune system a boost to prevent the lymphoma from returning after transplant. For patients with active T-cell lymphomas, two-year survival rates were 60%. However, even these lower rates are better than the historical norm of 30-50%, suggesting that the targeted T-cell therapies could help fight disease in patients with this poor prognosis lymphoma.

Dr. McLaughlin, the study’s lead author and a Lymphoma Research Foundation grantee, notes that researchers have more work to do before this treatment becomes mainstream. For example, this treatment will need to be tested in larger populations of patients with EBV-related lymphoma to determine who would derive the most benefit, the ideal dose and dose timing. It also may be possible to extend targeted T-cell treatments like this to other types of cancers. In the future, Dr. McLaughlin adds, it may be possible to develop T-cells that could be used “off the shelf”—in other words, they wouldn’t need to come from a matched donor and would be ready to use whenever a recipient needs them. Another future goal is using this therapy as one of the first lines of treatment rather than as a last resort.

“Our ultimate goal is to find a way to avoid chemotherapy and/or radiation therapy while still effectively treating a patient’s cancer,” she says. “Can you use the immune system to do that job? We’re working to answer that question.”

“Overall, children who receive kidney transplants had minimal concerns about quality of life after their operation. While it’s comforting that most pediatric patients had no significant problems, the range of quality of life scores indicate that some patients had remarkable difficulties,” says Kaushalendra Amatya, Ph.D., a pediatric psychologist in Nephrology and Cardiology at Children’s National and the study’s lead author.

About 2,000 children and adolescents younger than 18 are on the national waiting list for an organ transplant, according to the Department of Health and Human Services, with most infants and school-aged children waiting for a heart, liver or kidney and most children older than 11 waiting for a kidney or liver. In 2018, 1,895 U.S. children received transplants.

The research team at Children’s National wanted to hear directly from kids about their quality of life after kidney transplant in order to tailor timely interventions to children. Generally, recipients of kidney transplants have reported impaired quality of life compared with healthy peers, with higher mental health difficulties, disrupted sleep patterns and lingering pain.

The Children’s team measured general health-related quality of life using a 23-item PedsQL Generic Core module and measured transplant-related quality of life using the PedsQL- Transplant Module. The forms, which can be used for patients as young as 2, take about five to 10 minutes to complete and were provided to the child, the parent or the primary care giver – as appropriate – during a follow-up visit after the transplant.

Thirty-three patient-parent dyads completed the measures, with an additional 25 reports obtained from either the patient or the parent. The patients’ mean age was 14.2; 41.4% were female.

“Overall, children who receive kidney transplants had minimal concerns about quality of life after their operation. While it’s comforting that most pediatric patients had no significant problems, the range of quality of life scores indicate that some patients had remarkable difficulties,” says Kaushalendra Amatya, Ph.D., a pediatric psychologist in Nephrology and Cardiology at Children’s National and the study’s lead author.

When the study team reviewed reports given by parents, they found their descriptions sometimes differed in striking ways from the children’s answers.

“Parents report lower values on emotional functioning, social functioning and total core quality of life, indicating that parents perceive their children as having more difficulties across these specific domains than the patients’ own self reports do,” Amatya adds.

10th Congress of the International Pediatric Transplant Association presentation

“An exploration of health-related quality of life in pediatric renal transplant recipients.”

Emerging evidence links dnDSA with increased risk of accelerated systemic hardening of the arteries (arteriosclerosis) and major cardiac events in adult organ transplant recipients. However, this phenomenon has not been studied extensively in children who receive kidney transplants.

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Children who developed anti-human leukocyte antibodies against their donor kidney, known as de novo donor-specific antibodies (dnDSA), after kidney transplant were more likely to experience carotid intima-media thickening (CIMT) than those without these antibodies, according to preliminary research presented May 7, 2019, during the 10th Congress of the International Pediatric Transplant Association.

dnDSA play a key role in the survival of a transplanted organ. While human leukocyte antibodies protect the body from infection, dnDSA are a major cause of allograft loss. CIMT measures the thickness of the intima and media layers of the carotid artery and can serve as an early marker of cardiac disease.

Emerging evidence links dnDSA with increased risk of accelerated systemic hardening of the arteries (arteriosclerosis) and major cardiac events in adult organ transplant recipients. However, this phenomenon has not been studied extensively in children who receive kidney transplants.

To investigate the issue, Children’s researchers enrolled 38 children who had received kidney transplants and matched them by race with 20 healthy children. They measured their CIMT, blood pressure and lipids 18 months and 30 months after their kidney transplants. They monitored dnDSA at 18 months and 30 months after kidney transplant. The transplant recipients’ median age was 11.3 years, 50 percent were African American, and 21% developed dnDSA.

“In this prospective controlled cohort study, we compared outcomes among patients who developed dnDSA with transplant recipients who did not develop dnDSA and with race-matched healthy kids,” says Kristen Sgambat, Ph.D., a pediatric renal dietitian at Children’s National who was the study’s lead author. “Children with dnDSA after transplant had 5.5% thicker CIMT than those who did not have dnDSA. Being African American was also independently associated with a 9.2% increase in CIMT among transplant recipients.”

Additional studies will need to be conducted in larger numbers of pediatric kidney transplant recipients to verify this preliminary association, Sgambat adds.

10th Congress of the International Pediatric Transplant Association presentation:

Mutations in the NUP160 gene, which encodes one protein component of the nuclear pore complex nucleoporin 160 kD, are implicated in steroid-resistant nephrotic syndrome, an international team reports March 25, 2019, in the Journal of the American Society of Nephrology. Mutations in this gene have not been associated with steroid-resistant nephrotic syndrome previously.

“Our findings indicate that NUP160 should be included in the gene panel used to diagnose steroid-resistant nephrotic syndrome to identify additional patients with homozygous or compound-heterozygous NUP160 mutations,” says Zhe Han, Ph.D., an associate professor in the Center for Genetic Medicine Research at Children’s National and the study’s senior author.

The kidneys filter blood and ferry waste out of the body via urine. Nephrotic syndrome is a kidney disease caused by disruption of the glomerular filtration barrier, permitting a significant amount of protein to leak into the urine. While some types of nephrotic syndrome can be treated with steroids, the form of the disease that is triggered by genetic mutations does not respond to steroids.

The patient covered in the JASN article had experienced persistently high levels of protein in the urine (proteinuria) from the time she was 7. By age 10, she was admitted to a Shanghai hospital and underwent her first renal biopsy, which showed some kidney damage. Three years later, she had a second renal biopsy showing more pronounced kidney disease. Treatment with the steroid prednisone; cyclophosphamide, a chemotherapy drug; and tripterygium wilfordii glycoside, a traditional therapy, all failed. By age 15, the girl’s condition had worsened and she had end stage renal disease, the last of five stages of chronic kidney disease.

An older brother and older sister had steroid-resistant nephrotic syndrome as well and both died from end stage kidney disease before reaching 17. When she was 16, the girl was able to receive a kidney transplant that saved her life.

Han learned about the family while presenting research findings in China. An attendee of his session said that he suspected an unknown mutation might be responsible for steroid-resistant nephrotic syndrome in this family, and he invited Han to work in collaboration to solve the genetic mystery.

By conducting whole exome sequencing of surviving family members, the research team found that the mother and father each carry one mutated copy of NUP160 and one good copy. Their children inherited one mutated copy from either parent, the variant E803K from the father and the variant R1173X, which causes truncated proteins, from the mother. The woman (now 29) did not have any mutations in genes known to be associated with steroid-resistant nephrotic syndrome.

Some 50 different genes that serve vital roles – including encoding components of the slit diaphragm, actin cytoskeleton proteins and nucleoporins, building blocks of the nuclear pore complex – can trigger steroid-resistant nephrotic syndrome when mutated.

With dozens of possible suspects, they narrowed the list to six variant genes by analyzing minor allele frequency, mutation type, clinical characteristics and other factors.

Significantly, the dramatic structural and functional defects caused by silencing of fly Nup160 gene in nephrocytes could be completely rescued by expressing the wild-type human NUP160 gene, but not by expressing the human NUP160 gene carrying the E803K or R1173X mutation identified from the girl’s family.

“This study identified new genetic mutations that could lead to steroid-resistant nephrotic syndrome,” Han notes. “In addition, it demonstrates a highly efficient Drosophila-based disease variant functional study system. We call it the ‘Gene Replacement’ system since it replaces a fly gene with a human gene. By comparing the function of the wild-type human gene versus mutant alleles from patients, we could determine exactly how a specific mutation affects the function of a human gene in the context of relevant tissues or cell types. Because of the low cost and high efficiency of the Drosophila system, we can quickly provide much-needed functional data for novel disease-causing genetic variants using this approach.”

Financial support for research described in this post was provided by the Nature Science Foundation of Fujian Province of China, under grant 2015J01407; National Nature Science Foundation of China, under grant 81270766; Key Project of Social Development of Fujian Province of China, under grant 2013Y0072; and the National Institutes of Health, under grants DK098410 and HL134940.

African Americans who either donated a kidney, received a kidney donation, are on dialysis awaiting a kidney transplant or have a close relative in one of those categories are helping to perfect a new study that aims to improve outcomes after kidney transplantation.

The study is called APOLLO, short for APOL1 Long-Term Kidney Transplantation Outcomes Network. Soon, the observational study will begin to enroll people who access transplant centers around the nation to genotype deceased and living African American kidney donors and transplant recipients to assess whether they carry a high-risk APOL1 gene variant.

The study’s Community Advisory Council – African American stakeholders who know the ins and outs of kidney donation, transplantation and dialysis because they’ve either given or received an organ or are awaiting transplant – are opening the eyes of researchers about the unique views of patients and families.

Already, they’ve sensitized researchers that patients may not be at the same academic level as their clinicians, underscoring the importance of informed consent language that is understandable, approachable and respectful so people aren’t overwhelmed. They have encouraged the use of images and color to explain the apolipoprotein L1 (APOL1) gene. The APOL1 gene is found almost exclusively in people of recent African descent, however only 13 percent of these people carry the high-risk APOL1 variant that might cause kidney problems.

One issue arose early, during one of the group’s first monthly meetings, as they discussed when to tell patients and living donors about the APOLLO study. Someone suggested the day of the transplant.

“The Community Advisory Council told them that would not be appropriate. These conversations should occur well before the day of the transplant,” recalls Nichole Jefferson.

“The person is all ready to give a kidney. If you’re told the day of transplant ‘we’re going to include you in this study,’ that could possibly stop them from giving the organ,” Jefferson says. “We still remember the Tuskegee experiments. We still remember Henrietta Lacks. That is what we are trying to avoid.”

Patrick O. Gee, Ph.D., JLC, another Community Advisory Council member, adds that it’s important to consider “the mental state of the patient and the donor. As a patient, you know you are able to endure a five- to eight-hour surgery. The donor is the recipient’s hero. As the donor, you want to do what is right. But if you get this information; it’s going to cause doubt.”

Gee received his kidney transplant on April 21, 2017, and spent 33 days in the hospital undergoing four surgeries. His new kidney took 47 days to wake up, which he describes as a “very interesting journey.” Jefferson received her first transplant on June 12, 2008. Because that kidney is in failure, she is on the wait list for a new kidney.

“All I’ve ever known before APOLLO was diabetes and cardiovascular issues. Nobody had ever talked about genetics,” Gee adds. “When I tell people, I tread very light. I try to stay in my lane and not to come off as a researcher or a scientist. I just find out information and just share it with them.”

As he spoke during a church function, people began to search for information on their smart phones. He jotted down questions “above his pay grade” to refer to the study’s principal investigator. “When you start talking about genetics and a mutated gene, people really want to find out. That was probably one of the best things I liked about this committee: It allows you to learn, so you can pass it on.”

Jefferson’s encounters are more unstructured, informing people who she meets about her situation and kidney disease. When she traveled from her Des Moines, Iowa, home to Nebraska for a transplant evaluation, the nephrologist there was not aware of the APOL1 gene.

And during a meeting at the Mayo Clinic with a possible living donor, she asked if they would test for the APOL1 gene. “They stopped, looked at me and asked: ‘How do you know about that gene?’ Well, I’m a black woman with kidney failure.”

Patrick O. Gee received his kidney transplant on April 21, 2017, and spent 33 days in the hospital undergoing four surgeries. His new kidney took 47 days to wake up, which he describes as a “very interesting journey.”

About 100,000 U.S. children and adults await a kidney transplant. APOLLO study researchers believe that clarifying the role that the APOL1 gene plays in kidney-transplant failure could lead to fewer discarded kidneys, which could boost the number of available kidneys for patients awaiting transplant.

Gee advocates for other patients and families to volunteer to join the APOLLO Community Advisory Council. He’s still impressed that during the very first in-person gathering, all researchers were asked to leave the table. Only patients and families remained.

“They wanted to hear our voices. You rarely find that level of patient engagement. Normally, you sit there and listen to conversations that are over your head. They have definitely kept us engaged,” he says. “We have spoken the truth, and Dr. Kimmel is forever saying ‘who would want to listen to me about a genotype that doesn’t affect me? We want to hear your voice.’ ”

Jefferson encourages other people personally impacted by kidney disease to participate in the APOLLO study.

“Something Dr. Kimmel always says is ‘You’re in the room.’ We’re in the room while it’s happening. It’s a line from Hamilton. That’s a good feeling,” she says. “I knew right off, these are not necessarily improvements I will see in my lifetime. I am OK with that. With kidney disease, we have not had advances in a long time. As long as my descendants don’t have to go through the same things I have gone through, I figure I have done my part. I have done my job.”

https://innovationdistrict.childrensnational.org/wp-content/uploads/2019/03/APOLLO-1_Left-Nichole-Jefferson-right-Patrick-Gee.png300400Innovation Districthttps://innovationdistrict.childrensnational.org/wp-content/uploads/2018/11/idlogo1-tagline-Advances-in-Medicine.gifInnovation District2019-03-18 16:20:082019-03-18 16:51:21African American stakeholders help to perfect the APOLLO study

Test your knowledge of APOL1’s role in kidney health

Through the APOLLO study, Marva Moxey-Mims, M.D., FASN, and others hope that clarifying the role of the APOL1 gene in kidney-transplant failure leads to fewer discarded kidneys, improved outcomes after transplant and improved safety in living donations. Test your knowledge about kidney transplants in this quiz.

1. How many U.S. children and adults are waiting for a kidney transplant?

Mitochondria are the cell’s powerplants and inside them the MTP enzymatic complex catalyzes three steps in beta-oxidation of long-chain fatty acids.

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In one family, genetic lightning struck twice. Two sisters were diagnosed with mitochondrial trifunctional protein (MTP) deficiency. This is a rare condition that stops the body from converting fats to energy, which can lead to lactic acidosis, recurrent breakdown of muscle tissue and release into the bloodstream (rhabdomyolysis), enlarged heart (cardiomyopathy) and liver failure.

Mitochondria are the cell’s powerplants and inside them the MTP enzymatic complex catalyzes three steps in beta-oxidation of long-chain fatty acids. MTP deficiency is so rare that fewer than 100 cases have been reported in the literature says Hostensia Beng, M.D., who presented an MTP case study during the American Society of Nephrology’s Kidney Week.

The 7-month-old girl with known MTP deficiency arrived at Children’s National lethargic with poor appetite. Her laboratory results showed a low corrected serum calcium level, elevated CK level and protein in the urine (proteinuria) at a nephrotic range. The infant was treated for primary hypoparathyroidism and rhabdomyolysis.

Even though the rhabdomyolysis got better, the excess protein in the girl’s urine remained at worrisome levels. A renal biopsy showed minimal change disease and foot process fusion. And electron microscopy revealed shrunken, dense mitochondria in visceral epithelial cells and endothelium.

“We gave her tacrolimus, a calcineurin inhibitor that we are well familiar with because we use it after transplants to ensure patient’s bodies don’t reject the donated organ. By eight months after treatment, the girl’s urine protein-to-creatinine (uPCR) ratio was back to normal. At 35 months, that key uPCR measure rose again when tacrolimus was discontinued. When treatment began again, uPCR was restored to normal levels one month later,” Dr. Beng says.

The girl’s older sister also shares the heterozygous deletion in the HADHB gene, which provides instructions for making MTP. That missing section of the genetic how-to guide was predicted to cause truncation and loss of long-chain-3-hydroxyacl CoA dehydrogenase function leading to MTP deficiency.

“Renal involvement has been reported in only one patient with MTP deficiency to date, the older sister of our patient,” Dr. Beng adds.

Podocytes are specialized cells in the kidneys that provide a barrier, preventing plasma proteins from leaking into the urine. Podocytes, however, need energy to function and are rich in mitochondria.

“The proteinuria in these two sisters may be related to their mitochondrial dysfunction. Calcineurin inhibitors like tacrolimus have been reported to reduce proteinuria by stabilizing the podocyte actin cytoskeleton. Tacrolimus was an effective treatment for our patient, who has maintained normal renal function, unlike her sister,” Dr. Beng says.

A red badge allows newly diagnosed cancer patients and BMT patients to bypass security and triage so they can receive lifesaving antibiotics within an hour of fighting fever.

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Chemotherapy and bone marrow transplant procedures leave cancer patients with compromised immune systems, leading many to develop life-threatening infections or other complications. In particular, neutropenia, or abnormally low levels of white blood cells that are critical to fighting off infections, is prevalent among this population. Fever with neutropenia can be fatal.

As part of the Children’s National Health System commitment to deliver better outcomes and safer care through innovative approaches, the Hematology/Oncology/Bone Marrow Transplant (BMT) Family Advisory team developed a protocol to rapidly identify BMT and cancer patients with suspected neutropenia to receive antibiotics within 60 minutes of arriving at the Emergency Department (ED). The Red Badge Project was born with the following goals:

• Decrease the median triage-to-antibiotic time in cancer patients with fever and suspected neutropenia or bone marrow transplant patients to 30 minutes
• Increase the proportion of patients receiving antibiotics within one hour to 90 percent

As part of the protocol, newly diagnosed cancer and bone marrow transplant patients receive a Red Badge and education regarding how to use it. If they run a fever and need medical attention, the patient and family present the Red Badge upon arrival at the ED in order to bypass the welcome desk and ED triage. This action accelerates the process, keeps the child from waiting in an area where there are other sick children and ensures the patient receives lifesaving antibiotics as fast as possible.

Work done before the patient walks through the ED doors contributes to the success of this program. When a patient runs a fever, the family is instructed to call the Hematology Oncology Fellow on-call. If it is determined that the patient needs to come to the ED, the Fellow then: 1) receives the patient’s estimated arrival time so that staff can clean and prep a room 2) reminds them to apply their topical analgesia to numb the port site where the antibiotic will be administered 3) reminds them to bring their Red Badge.

From there, swift action is taken. By the time the patient arrives, he or she has already been registered and the appropriate medications have been ordered. The patient bypasses security and triage using their Red Badge as a visual cue and is then directed to a prepped room complete with medications ready for administration.

To date, the median time from triage to administration of antibiotics has decreased nearly 50 percent while the proportion of patients who received antibiotics within 60 minutes of triage improved to 90 percent.

Leveraging that success, the next step is to develop education for non-English speaking families in order to extend the reach of this lifesaving practice.

Intestinal failure often prevents these patients from digesting enough nutrients and fluids to maintain proper growth, and they often require parenteral nutrition (PN). Dr. Torres’ team has helped to wean 91.3 percent of patients from PN, compared with the above study, which showed that enteral autonomy was achieved in 43 percent.

Based on the outcomes for the first 120 children with SBS treated in Children’s National’s IRP from 2007 to 2016, Dr. Torres says that with meticulous and aggressive medical/surgical management, even patients with advanced liver disease can show improvement in liver functions and nutritional parameters with the ability to discontinue parenteral nutrition and avoid the need for transplantation.

“These are very, very good results for any program and ours has been growing substantially in the last 10 years,” Dr. Torres says. “We are like a family, we are very good at teaching so everyone knows how to care for these patients.”

Cross-departmental collaboration

Her main focus as director has been spreading the word about SBS across the departments. For example, the ER knows to start IV fluids on these patients right away or to keep watch for sepsis symptoms. From nurses, pediatric residents, and surgeons to radiologists and the ER, Dr. Torres has encouraged the sharing of knowledge and teaching how to respond to SBS patients.

Dr. Torres also attributes the success of the Children’s National’s program to having a multidisciplinary intestinal rehabilitation team who are trained to follow up with these highly complex patients with SBS. “In general, these patients have a very high morbidity-mortality rate, and it’s important to be close to follow up.”

Other important members are one physician assistant, two nurse practitioners, two coordinators, one dietitian, one social worker, one case manager, and devoted nurses who work in the specialized Intestinal Rehabilitation Unit.

Having a dedicated director and surgeon also is a new perspective. Focusing on this group of patients allows Drs. Torres and Sandler to become experts in the medical and surgical management of the patients with short bowel and intestinal failure.

A closer look inside the program

The goal of the IRP is to optimize bowel function through the use of multiple therapies and to eventually wean patients with intestinal failure from parenteral nutrition. The medical treatment focuses on comprehensive dietary management with very precise control of metabolic balance and prompt and effective treatment of complications.

The use of specialized enteral feeding programs by the experience medical team helps to maintain nutrition and hydration, which are important factors in long-term survival. Other important components of the program are ongoing parent education and support, and promoting an optimal quality of life. Intestinal transplantation with MedStar Georgetown University Hospital is an option for patients who fail treatment.

“The Intestinal Rehabilitation at Children’s National provides children with intestinal failure the chance to receive comprehensive medical and surgical care, giving them the chance for improved long-term survival, including weaning from parenteral nutrition and avoidance of the need for transplantation and long-term immunosuppression,” Dr. Torres says.

New research shows the effectiveness of an Advance Care Planning model developed through participatory research with adolescents in improving palliative care among adult people living with #HIV
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